I've got $$$$$ that is where you find the short. 
ENG SEN fuse....
ENG SEN fuse.... My car keeps blowing it. Been firing the car on/off for the last couple days to test a window switch. Everything has been 100% normal. Went out this morning, fired the car up a couple times and it was fine. Went back out a couple hours ago and I noticed I had lost power from a switched source that I had in the IGN fuse hole in the car. Hmm....messed around a bit and then went to start the car, nothing. Won't spin over or anything. Checked the fuses and seen that the ENG SEN was fried. Swapped it out, went to fire the car up, fried another one. They are burning out as soon as the key is turned to the ACC position. I thought it may have been something in the brakes, as I tapped into the brake lights for my window switch, but they all test normal when the key is in the ACC. So I'm assuming it has nothing to do with it.
I swapped my MAF to my stock one. Checked all the connections to it. Looked around the headers for burnt wires....can't find anything out of the usual.
I was already good and pissed off over the window switch/transbrake junk, this just adds to the heap of ****. Anyone wanna buy a car? HELP!
I swapped my MAF to my stock one. Checked all the connections to it. Looked around the headers for burnt wires....can't find anything out of the usual.
I was already good and pissed off over the window switch/transbrake junk, this just adds to the heap of ****. Anyone wanna buy a car? HELP!
hmmmm....i was going to say check your o2 extention on your headers. i've done that and pissed me off good for a while. if it's not that there has to be another wire somewhere touching something. sorry couldn't be of more help.
If a fuse blows immediately you have a dead SHORT to ground(pinched wire touching metal, bare wire touching metal, etc. This has to be a HOT wire that hasn't reached its' LOAD yet. The LOAD is being bypassed where the HOT wire is touching your chassis. It's call a SHORT because the LOAD gets bypassed when the current takes a shorter path to ground than it would have to take if it went through the LOAD like it's supposed to do. You can do this one of two ways depending on how many spare fuses you have. You can take the advice given you by2001NBMZ28 and disconnect everything that you think is remotely involved with this circuit. Start plugging things back in one at a time checking the fuse each time you plug together a connector. When the fuse blows you've found the offending circuit. OR you can start DISCONNECTING the connectors until the fuse stops blowing. This method will use up more fuses, but you don't have to unplug as many things initially. With this method if the fuse does NOT blow you reconnect that particular connector and move on to the next one. At this point your troubleshooting has just begun, but at least you have a starting point. Now you need a schmatic to find out where all the wires in this particular circuit go. You'll have to trace them all out using a DVOM until you find a wire at ground potential that should normally be HOT. I'd start looking in areas you recently worked just before this fuse started blowing. A bright LED flashlite would help at this point to see the short. Look closey at pinch points(areas around moving parts) or for chaffed wires.
Last edited by eallanboggs; Mar 18, 2007 at 07:58 PM.
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Originally Posted by 2001NBMZ28
That was my first thought also - time to disconnect things one at a time to find out what it is. Don't think a fried ENG SEN fuse alone would keep the car from turning over?
I knew my MAF was bad and the car had been idling rough/running rough, so I might have blown the ENG SEN fuse long before these problems and I just never looked, as I haven't driven the car in a while.
So....what else could it be? No one else seems to have their car not turn over at all b/c of that fuse, so I'm guessing it's something else.
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TECH Senior Member
Joined: Dec 2001
Posts: 5,399
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From: Jacksonville, FL
Man I don't know. Did you disconnect whatever you had plugged into the IGN inside the car? Also wondering if the IGN port inside the car is connected somehow to the IGN in fuse/relay center 2 under the hood cause that controls ignition switch, relay and starter enable relay. Just guessing...
First of all lets get one thing straight. This is a fishing expedition. If you don't know where the fish are you have to hunt for them first before you can catch them. Just looking "at the 02 sensors" doesn't remove them from the circuit. That's what connectors are for. Have you gone over EVERYTHING you worked on before this fuse started blowing? Apparently NOT! You don't have to remove a different relay to use it as a test in another position. You can probe the coil circuit instead with your DVOM. Troubleshoot your IGN circuit. With the fuse removed or BLOWN in this case make sure no wires that are normally HOT are at ground potential. You havn't opened up enough connectors yet. When you open the right one the fuse is going to stop blowing. That's when the real work begins of tracing out individual wires. Go Fish!
What connectors are left? The only thing, according to the manual, are the o2 sensors, which appear fine. Even if they were bad, it wouldn't completely disable power to the motor. The motor never even hints to want to turn over. It's just a dead fire.
I unhooked my window switch, which the install of that is pretty much when this started happening, and still nothing. I had spliced into the wrong brake wire. The wire gave signal when the brakes were not pressed and lost signal when the brakes were pressed. I unhooked all that, and still nothing. I know it was the wrong wire now, but that still had nothing to do with what's happening.
This seems to be a one of a kind mishap because I can't find any other occurnace of this on tech through search...
I unhooked my window switch, which the install of that is pretty much when this started happening, and still nothing. I had spliced into the wrong brake wire. The wire gave signal when the brakes were not pressed and lost signal when the brakes were pressed. I unhooked all that, and still nothing. I know it was the wrong wire now, but that still had nothing to do with what's happening.
This seems to be a one of a kind mishap because I can't find any other occurnace of this on tech through search...
Some power wires also have what is known as a "fusible" link in to protect the car in the case of a direct short before the fusebox. I can't tell you where to look just giving some more possibilities for no power to the ign circuit. Keep searching.....
A "fuseable link" is like a MASTER circuit breaker. It would be the highest rated fuse in the vehicle. If it blows you're D.O.A. I believe he has some power on certain circuits. It may be time to consult your local priest for some holy water or bite the bullet and pull out your wallet to let the pros have a crack at it. Fishing expeditions are never cheap especially if you're fishng with a blindfold on.
Have you removed the accessories you recently added, the
window switch etc. from the circuit? It might be a short or
it might be that the total load is just on the wrong side of
the fuse current capacity.
You might want to pick up a blade-style circuit breaker and
swap it in, one of the same rating. It will cycle and reset and
if you're under the car maybe the sparks will make enough
noise to find by ear if it's a real short. Our interior fuse panel
is too short for breakers with the lid on but engine bay, you
could probably get by (and never have to buy fuses again).
I'd chase around the engine wiring harness by hand from
above and below, follow the O2 sensors' harnesses all the way
up feeling for melt / butrn spots etc., look for pinched wires
near where you tapped in for window switch power and so on.
For adding a lot of electrical load Ilike nitrous systems can
want) you're probably best off adding a circuit breaker and
relay off the BAT circuit with the coil energized by IGN. This
unloads the main IGN relay and feeds big time, keeps all the
"new stuff" on its own branch where any oopses won't bother
the engine power etc.
window switch etc. from the circuit? It might be a short or
it might be that the total load is just on the wrong side of
the fuse current capacity.
You might want to pick up a blade-style circuit breaker and
swap it in, one of the same rating. It will cycle and reset and
if you're under the car maybe the sparks will make enough
noise to find by ear if it's a real short. Our interior fuse panel
is too short for breakers with the lid on but engine bay, you
could probably get by (and never have to buy fuses again).
I'd chase around the engine wiring harness by hand from
above and below, follow the O2 sensors' harnesses all the way
up feeling for melt / butrn spots etc., look for pinched wires
near where you tapped in for window switch power and so on.
For adding a lot of electrical load Ilike nitrous systems can
want) you're probably best off adding a circuit breaker and
relay off the BAT circuit with the coil energized by IGN. This
unloads the main IGN relay and feeds big time, keeps all the
"new stuff" on its own branch where any oopses won't bother
the engine power etc.
i had this happen once also with blowing the fuse and what i found mine to be was the wires going into the MAF sensor plug on the harness were pinched and shorting out...fixed the wires and never happened again
JR
JR
Alright guys, thanks for all the input. I went and got a Haynes manual today and traced all the wiring that has the ENG SEN fuse on it. I've unhooked the MAF, the brake switch, and the both o2's...I'm still burning up that fuse. I was looking at the wiring diagrams in my manual and was trying to search for the IGN fuse in the interior fuse box. According to what I looked up, it has nothing to do with the ENG SEN fuse. I'm getting no power to my IGN relay, which has to be activated to let anything with the ENG SEN fuse operate. I think I've blown the fuse in the interior IGN fuse box.
Anyone have any ideas about that?
Anyone have any ideas about that?
You can unhook all the sensors you want but if one of the hot wires that would go to the sensor is touching any metal on the car the fuse will still blow. Look for an exposed conductor on all your wires.
make sure you check out your trannys reverse and 1-4 shift solenoids, they are connected to that fuse too.
make sure you check out your trannys reverse and 1-4 shift solenoids, they are connected to that fuse too.
I know they're connected, but my car was originally an auto, so I shouldn't have them. I thought if I disconnected the connectors, then they wouldn't react in that circuit...at least that's what everyone on here said.
I'm gonna try and swap out the IGN fusible link tomorrow and see if that works. Even with that fuse blowing, it has nothing to do with the IGN fuse inside the car, which is what had me stumped from the get go. Now that I have a wiring diagram, it's making things a bit easier.
I'm gonna try and swap out the IGN fusible link tomorrow and see if that works. Even with that fuse blowing, it has nothing to do with the IGN fuse inside the car, which is what had me stumped from the get go. Now that I have a wiring diagram, it's making things a bit easier.